Tehran, Feb 20 : Iran's first genetically modified (GM) rice has been approved by national authorities and is currently being grown commercially for human consumption.

Researchers at the Agricultural Biotechnology Research Institute of Iran (ABRII) modified rice to resist attack by insects by inserting a bacterial gene that produces a toxin.

The chemical kills insects but is harmless to birds and mammals, reports science portal SciDev.net.

The research was conducted in collaboration with the Philippines-based International Rice Research Institute (IRRI) using a local variety of aromatic rice, Tarom molaii.

Following laboratory tests, the GM rice was grown in a greenhouse and in field experiments from 1999 to October 2004 - a total of six generations.

During the trials, the GM rice killed close to 100 percent of the four species of insect pests attempting to feed on it, ABRII director general Behzad Ghareyazie was quoted as saying.

One of these - the striped stem borer - is the main insect pest of rice in Iran and is also widespread in Asia, where it can cause substantial crop losses.

Ghareyazie added that in the field trials, the GM rice showed no abnormal patterns of growth and differed from non-GM rice only in its ability to resist pests.

Additional tests showed that the modified rice had the same nutritional value as the variety it was developed from, he said.

Livestock too accepted the GM rice and had no adverse health effects from eating it, said Ghareyazie.

The results of the field trials and animal feeding experiments are now being prepared for publication.

Iran is one of the world's major importers of rice.

According to Mohammed Hamoud, head of genetic research in the botany department of Tanta University, Egypt, the Iranian rice could provide a cost-effective way of controlling pests, as well as being environmentally friendly because it would decrease pesticide use.

He however added that the rice should undergo more careful testing to ensure it is safe for human consumption and to minimise environmental risks, such as the development of resistance in the pests to the toxin in the rice.

In addition to GM rice, Iran has produced several GM plants in the laboratory, such as insect-resistant maize, cotton, potato and sugar beet; herbicide-resistant canola; salinity- and drought- tolerant wheat; and blight-resistant maize and wheat.

Greenhouse and field tests experiments are being conducted on these crops.